feat: T6.1 创作工具箱通用生成器框架地基 — 脑洞生成器 + run_generator

- schemas: Idea/IdeaListResult（脑洞生成器结构化产出，纯预览不入库）
- specs: brainstorm_spec（light 档，reads=[projects] writes=[]）
- orchestrator: build_brief_context（brief_only 策略）+ 通用 run_generator
  （据 spec.output_schema 校验 parsed，不绑定具体类型，任一声明式生成器共用）
- 新增 13 测；两包 ruff/format/mypy 干净、252 passed 无回归

P1 第一波（@llm）：证实「加生成器=加一份声明」。@backend T6.2/T6.3 待续。

packages/core/tests/test_generator_node.py

@@ -0,0 +1,91 @@
+"""T6 通用生成器执行器单测：`run_generator` + `build_brief_context`。
+
+注入 mock 网关（产 IdeaListResult parsed），无真 LLM、无真 Postgres。通用执行器据
+`spec.output_schema` 校验 parsed（不绑定具体类型）；只产结构化产物，**不写库**（纯预览，
+不变量 #3）。asyncio_mode=auto。
+"""
+
+from __future__ import annotations
+
+import uuid
+
+import pytest
+from fakes_orchestrator import FailingRunGateway, FakeRunGateway
+from ww_agents import Idea, IdeaListResult, brainstorm_spec
+from ww_core.orchestrator import build_brief_context, run_generator
+
+PROJECT = uuid.UUID("00000000-0000-0000-0000-000000000001")
+USER = uuid.UUID("00000000-0000-0000-0000-0000000000aa")
+
+_IDEAS = IdeaListResult(
+    ideas=[
+        Idea(premise="废柴觉醒吞噬瞳", hook="升级要付记忆", genre_fit="玄幻"),
+        Idea(premise="末世种粮农场主", hook="粮食成硬通货"),
+    ]
+)
+
+
+# ---- run_generator：返回结构化产物，据 output_schema 校验，只读不写库 ----
+
+
+async def test_run_generator_returns_structured_result() -> None:
+    gateway = FakeRunGateway(_IDEAS)
+
+    result = await run_generator(
+        brainstorm_spec,
+        context=build_brief_context(brief="来点逆袭流", project_context="题材：玄幻"),
+        gateway=gateway,
+        user_id=USER,
+        project_id=PROJECT,
+    )
+
+    assert isinstance(result, IdeaListResult)
+    assert len(result.ideas) == 2
+    assert result.ideas[0].premise == "废柴觉醒吞噬瞳"
+
+
+async def test_run_generator_passes_tier_and_schema_to_gateway() -> None:
+    # 不变量 #2：只透传档位（light），不传 model；output_schema 据 spec 绑定
+    gateway = FakeRunGateway(_IDEAS)
+
+    await run_generator(
+        brainstorm_spec,
+        context="x",
+        gateway=gateway,
+        user_id=USER,
+        project_id=PROJECT,
+    )
+
+    assert gateway.last_request is not None
+    assert gateway.last_request.tier == "light"
+    assert gateway.last_request.output_schema is IdeaListResult
+
+
+async def test_run_generator_raises_on_gateway_failure() -> None:
+    # 独立生成：网关失败直接上抛（端点处理），不静默吞
+    gateway = FailingRunGateway(RuntimeError("boom"))
+
+    with pytest.raises(RuntimeError, match="boom"):
+        await run_generator(
+            brainstorm_spec,
+            context="x",
+            gateway=gateway,
+            user_id=USER,
+            project_id=PROJECT,
+        )
+
+
+# ---- build_brief_context：确定性、空需求降级占位 ----
+
+
+def test_build_brief_context_is_deterministic() -> None:
+    a = build_brief_context(brief="逆袭", project_context="题材：玄幻")
+    b = build_brief_context(brief="逆袭", project_context="题材：玄幻")
+    assert a == b
+    assert "题材：玄幻" in a
+    assert "逆袭" in a
+
+
+def test_build_brief_context_empty_brief_falls_back() -> None:
+    ctx = build_brief_context(brief="   ", project_context="题材：都市")
+    assert "按题材自由发散" in ctx

packages/core/ww_core/orchestrator/__init__.py

@@ -21,11 +21,13 @@ from .collect import (
     extract_style,
 )
 from .generation_node import (
+    build_brief_context,
     build_character_gen_context,
     build_precheck_context,
     build_worldbuilder_context,
     precheck_generated_cards,
     run_character_gen,
+    run_generator,
     run_worldbuilder,
 )
 from .graph import (
@@ -102,6 +104,7 @@ __all__ = [
     "GatewayStream",
     "ReviewRecorder",
     "SseEvent",
+    "build_brief_context",
     "build_character_gen_context",
     "build_outline_request",
     "build_precheck_context",
@@ -128,6 +131,7 @@ __all__ = [
     "pace_event",
     "precheck_generated_cards",
     "run_character_gen",
+    "run_generator",
     "run_outline",
     "run_review",
     "run_style_extraction",

packages/core/ww_core/orchestrator/generation_node.py

@@ -28,6 +28,7 @@ from collections.abc import Sequence
 from typing import Protocol
 
 import structlog
+from pydantic import BaseModel
 from ww_agents import (
     AgentSpec,
     CharacterCard,
@@ -73,6 +74,49 @@ def _build_request(
     )
 
 
+# ---- 通用生成器执行器（T6 · 创作工具箱通用框架）----
+
+
+def build_brief_context(*, brief: str, project_context: str) -> str:
+    """通用「brief_only」上下文：作品设定 + 作者一句话需求（确定性，无时间戳）。
+
+    覆盖最简生成器（脑洞/书名…）：仅需作品设定 + 一句话方向。需求为空时给降级占位，
+    交由 system_prompt 的「按题材自由发散」纪律处理。
+    """
+    brief_block = brief.strip() or "（作者未填具体方向，按题材自由发散）"
+    return f"## 作品设定\n{project_context or '（暂无设定）'}\n\n## 创作需求\n{brief_block}"
+
+
+async def run_generator(
+    spec: AgentSpec,
+    *,
+    context: str,
+    gateway: GatewayRun,
+    user_id: uuid.UUID,
+    project_id: uuid.UUID,
+) -> BaseModel:
+    """通用生成器执行器（T6）：构请求 → `gateway.run` → 按 `spec.output_schema` 校验 parsed。
+
+    任一声明式生成器共用此路径（不绑定具体产物类型，据 spec 的 output_schema 校验）。
+    **只读、不写库**（纯预览，不变量 #3）；独立生成——网关失败直接上抛（端点处理），不静默吞。
+    """
+    expected = spec.output_schema
+    if expected is None:
+        raise ValueError(f"generator spec {spec.name!r} has no output_schema")
+    req = _build_request(spec, context=context, user_id=user_id, project_id=project_id)
+    resp = await gateway.run(req)
+    parsed = resp.parsed
+    if not isinstance(parsed, expected):
+        log.error(
+            "generator_node_missing_parsed",
+            spec=spec.name,
+            project_id=str(project_id),
+            parsed_type=type(parsed).__name__,
+        )
+        raise ValueError(f"gateway returned no parsed {expected.__name__} for {spec.name} request")
+    return parsed
+
+
 # ---- worldbuilder ----